The SMTP module immediately (on the first Router call) accepts messages addressed to domain name-wakeup local addresses. When these messages are enqueued into the SMTP module queue, they are processed as wake-up requests for the domain name domain message queue.
The SMTP module also immediately accepts all addresses with IP-address domains, i.e. with domain names like [xx.yy.zz.tt]. Please note that the Router adds brackets to the IP-address domain names that do not have them, and the Router changes the IP addresses of local domains to those domain names. The Router performs these operations before calling the modules.
The SMTP module immediately accepts addresses that have domain parts ending with the ._smtp suffix. This suffix is processed in the same way as the ._via suffix.
The SMTP module immediately accepts addresses that have domain parts ending with the ._smtpq suffix. This suffix is processed in the same way as the ._relay suffix.
On the final call, the SMTP module accepts mail to any domain if that domain name contains at least one dot (.) symbol. If the Forward option is selected, all these addresses are rerouted to the specified Forwarding Server domain.
Before accepting an address, the SMTP module checks if the address does not contain any @ symbol, but contains one or several % symbols. In this case, the rightmost % symbol is changed to the @ symbol.